The objective of this proposal is to establish a bioassay for high throughput screening of plant extracts and compounds against tuberculosis. The assay will be used for screening the flora of Puerto Rico for potential bioactives against these mycobacteria. Endemic and rare plant species as well as plants belonging to genera reported to have anti-tuberculosis activity will be assigned highest priority. In addition, detailed fractionation of the most active six plants found so far (against tuberculosis) will be carried out, and the active will be identified and characterized. The research will be carried out by the P.I., a research associate and a medical technologist. The assay will complement an ongoing anti-HIV/cytotoxic screen, thus increasing the likelihood of discovering potential leads against three important diseases. Graduate and undergraduate students will be involved in the research program under the supervision of the P.I. .